1. Field of the Invention
The present invention relates generally to conveyors, and specifically to ratchet type conveyors for moving various load carrying means, such as, wheeled carts and dollies, skids, pallets and the like.
2. Background
Various load carrying means, such as, wheeled carts and dollies, skids, and pallets are known in the art. Transporting and handling large numbers of such load carrying means in an organized manner either in a loaded or unloaded condition or both, is required in large automated material warehousing and supply facilities. Conveying means are known, such as, ratchet conveyors and chain conveyors, that are used to transport these load carrying devices. As is known in the art, chain conveyors provide for friction between, for example, the wheels of a cart wherein the continuous chain conveys the cart in a linear direction. Ratchet conveyors, typically hydraulic cylinder driven, provide for a back and forth motion wherein gravity dogs or other such intermittent contact means, are secured to a moveable bar, and move and are carried thereby in a back and forth alternate motion to intermittently push the load carrying means forward a certain distance with each extension stroke of the cylinder.
Both such conveying means are designed to move a load carrying means in a linear direction. A problem arises when a cart, or the like, must be conveyed through a curve, for example, around a 90 degree bend. Such change of direction has heretofore required expensive systems, such as turntables. In addition to being expensive, such change of direction systems do not provide for a continuous movement of the load carrying means.
Accordingly, it would be desirable to have a conveying system for load carrying means that provides for continuous movement thereof through a curve.